# Maintainer: Natanael Copa <ncopa@alpinelinux.org>

_flavor=lts
pkgname=linux-$_flavor
pkgver=6.6.59
_kernver=${pkgver%.*}
pkgrel=0
pkgdesc="Linux lts kernel"
url="https://www.kernel.org"
depends="initramfs-generator"
_depends_dev="perl gmp-dev mpc1-dev mpfr-dev elfutils-dev bash flex bison zstd"
makedepends="$_depends_dev sed installkernel bc linux-headers linux-firmware-any openssl-dev>3 mawk
	diffutils findutils zstd pahole python3 gcc>=13.1.1_git20230624"
options="!strip !check"
_config=${config:-config-lts.${CARCH}}
source="https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/linux-$_kernver.tar.xz
	0001-powerpc-boot-wrapper-Add-z-notext-flag-for-ppc64le.patch
	0002-x86-Compress-vmlinux-with-zstd-19-instead-of-22.patch
	0003-kexec-add-kexec_load_disabled-boot-option.patch
	0004-objtool-respect-AWK-setting.patch
	0005-powerpc-config-defang-gcc-check-for-stack-protector-.patch
	0006-LoongArch-Change-SHMLBA-from-SZ_64K-to-PAGE_SIZE.patch

	lts.aarch64.config
	lts.armv7.config
	lts.x86.config
	lts.x86_64.config
	lts.ppc64le.config
	lts.s390x.config
	lts.loongarch64.config

	virt.aarch64.config
	virt.armv7.config
	virt.ppc64le.config
	virt.x86.config
	virt.x86_64.config
	"
subpackages="$pkgname-dev:_dev:$CBUILD_ARCH $pkgname-doc"
for _i in $source; do
	case $_i in
	*.$CARCH.config)
		_f=${_i%."$CARCH".config}
		_flavors="$_flavors $_f"
		if [ "linux-$_f" != "$pkgname" ]; then
			subpackages="$subpackages linux-$_f::$CBUILD_ARCH linux-$_f-dev:_dev:$CBUILD_ARCH"
		fi
		;;
	esac
done
builddir="$srcdir"/linux-$_kernver

if [ "${pkgver%.0}" = "$pkgver" ]; then
	# Prepend to apply first
	source="patch-$pkgver.patch.xz::https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/patch-$pkgver.xz $source"
fi
arch="all !armhf !riscv64"
license="GPL-2.0-only"

# secfixes:
#   5.10.4-r0:
#     - CVE-2020-29568
#     - CVE-2020-29569
#   5.15.74-r0:
#     - CVE-2022-41674
#     - CVE-2022-42719
#     - CVE-2022-42720
#     - CVE-2022-42721
#     - CVE-2022-42722
#   6.1.27-r3:
#     - CVE-2023-32233
#   6.6.13-r1:
#     - CVE-46838

prepare() {
	default_prepare

	# remove localversion from patch if any
	rm -f localversion*
}

_kernelarch() {
	local arch="$1"
	case "$arch" in
		aarch64*) arch="arm64" ;;
		arm*) arch="arm" ;;
		ppc*) arch="powerpc" ;;
		s390*) arch="s390" ;;
		riscv*) arch="riscv" ;;
		loongarch64) arch="loongarch" ;;
	esac
	echo "$arch"
}

_prepareconfig() {
	local _flavor="$1"
	local _arch="$2"
	local _config=$_flavor.$_arch.config
	local _builddir="$srcdir"/build-$_flavor.$_arch
	mkdir -p "$_builddir"
	echo "-$pkgrel-$_flavor" > "$_builddir"/localversion-alpine

	cp "$srcdir"/$_config "$_builddir"/.config
	msg "Configuring $_flavor kernel ($_arch)"
	make -C "$builddir" \
		O="$_builddir" \
		ARCH="$(_kernelarch $_arch)" \
		olddefconfig

	if grep "CONFIG_MODULE_SIG=y" "$_builddir"/.config >/dev/null; then
		if [ -f "$KERNEL_SIGNING_KEY" ]; then
			sed -i -e "s:^CONFIG_MODULE_SIG_KEY=.*:CONFIG_MODULE_SIG_KEY=\"$KERNEL_SIGNING_KEY\":" \
				"$_builddir"/.config
			msg "Using $KERNEL_SIGNING_KEY to sign $_flavor kernel ($_arch) modules"
		else
			warning "KERNEL_SIGNING_KEY was not set. A signing key will be generated, but 3rd"
			warning "party modules can not be signed"
		fi
	fi
}

listconfigs() {
	for i in $source; do
		case "$i" in
			*.config) echo $i;;
		esac
	done
}

prepareconfigs() {
	for _config in $(listconfigs); do
		local _flavor=${_config%%.*}
		local _arch=${_config%.config}
		_arch=${_arch#*.}
		local _builddir="$srcdir"/build-$_flavor.$_arch
		_prepareconfig "$_flavor" "$_arch"
	done
}

# this is supposed to be run before version is bumped so we can compare
# what new kernel config knobs are introduced
prepareupdate() {
	clean && fetch && unpack && prepare && deps
	prepareconfigs
	rm -r "$builddir"
}

updateconfigs() {
	if ! [ -d "$builddir" ]; then
		deps && fetch && unpack && prepare
	fi
	for _config in ${CONFIGS:-$(listconfigs)}; do
		msg "updating $_config"
		local _flavor=${_config%%.*}
		local _arch=${_config%.config}
		_arch=${_arch#*.}
		local _builddir="$srcdir"/build-$_flavor.$_arch
		mkdir -p "$_builddir"
		echo "-$pkgrel-$_flavor" > "$_builddir"/localversion-alpine
		local actions="listnewconfig oldconfig"
		if ! [ -f "$_builddir"/.config ]; then
			cp "$srcdir"/$_config "$_builddir"/.config
			actions="olddefconfig"
		fi
		env | grep ^CONFIG_ >> "$_builddir"/.config || true
		make -j1 -C "$builddir" \
			O="$_builddir" \
			ARCH="$(_kernelarch $_arch)" \
			$actions savedefconfig

		cp "$_builddir"/defconfig "$startdir"/$_config
	done
}

set_kbuild_timestamp() {
	# KBUILD_BUILD_TIMESTAMP needs to be parsable by busybox date
	export KBUILD_BUILD_TIMESTAMP="$(date '+%Y-%m-%d %H:%M:%S' -u${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"
}

build() {
	unset LDFLAGS
	# for some reason these sometimes leak into the kernel build,
	# -Werror=format-security breaks some stuff
	unset CFLAGS CPPFLAGS CXXFLAGS
	set_kbuild_timestamp
	for i in $_flavors; do
		_prepareconfig "$i" "$CARCH"
	done
	for i in $_flavors; do
		msg "Building $i kernel"
		cd "$srcdir"/build-$i.$CARCH

		# set org in cert for modules signing
		# https://www.kernel.org/doc/html/v6.1/admin-guide/module-signing.html#generating-signing-keys
		mkdir -p certs
		sed -e 's/#O = Unspecified company/O = alpinelinux.org/' \
			"$builddir"/certs/default_x509.genkey \
			> certs/x509.genkey

		make ARCH="$(_kernelarch $CARCH)" \
			CC="${CC:-gcc}" \
			AWK="${AWK:-mawk}" \
			KBUILD_BUILD_VERSION="$((pkgrel + 1 ))-Alpine"
	done
}

_package() {
	local _buildflavor="$1" _outdir="$2"
	set_kbuild_timestamp

	cd "$srcdir"/build-$_buildflavor.$CARCH
	local _abi_release="$(make -s kernelrelease)"
	# modules_install seems to regenerate a defect Modules.symvers on s390x. Work
	# around it by backing it up and restore it after modules_install
	cp Module.symvers Module.symvers.backup

	mkdir -p "$_outdir"/boot "$_outdir"/lib/modules

	local _install
	case "$CARCH" in
		arm*|aarch64|riscv*) _install="zinstall dtbs_install";;
		*) _install=install;;
	esac

	make modules_install $_install \
		ARCH="$(_kernelarch $CARCH)" \
		INSTALL_MOD_PATH="$_outdir" \
		INSTALL_MOD_STRIP=1 \
		INSTALL_PATH="$_outdir"/boot \
		INSTALL_DTBS_PATH="$_outdir/boot/dtbs-$_buildflavor"

	cp Module.symvers.backup Module.symvers

	rm -f "$_outdir"/lib/modules/"$_abi_release"/build \
		"$_outdir"/lib/modules/"$_abi_release"/source
	rm -rf "$_outdir"/lib/firmware

	install -D -m644 include/config/kernel.release \
		"$_outdir"/usr/share/kernel/$_buildflavor/kernel.release

	case "$CARCH" in
	loongarch64)
		mv  "$_outdir"/boot/vmlinuz-$_abi_release \
			"$_outdir"/boot/vmlinuz-$_buildflavor

		mv  "$_outdir"/boot/config-$_abi_release \
			"$_outdir"/boot/config-$_buildflavor

		mv  "$_outdir"/boot/System.map-$_abi_release \
			"$_outdir"/boot/System.map-$_buildflavor
		;;
	esac
}

# main flavor installs in $pkgdir
package() {
	depends="$depends linux-firmware-any"

	_package "$_flavor" "$pkgdir"

	# copy files for linux-lts-doc sub package
	mkdir -p "$pkgdir"/usr/share/doc
	cp -r "$builddir"/Documentation \
		"$pkgdir"/usr/share/doc/linux-doc-"$pkgver"/
	# remove files that aren't part of the documentation itself
	for nondoc in \
		.gitignore conf.py docutils.conf \
		dontdiff Kconfig Makefile
	do
		rm "$pkgdir"/usr/share/doc/linux-doc-"$pkgver"/"$nondoc"
	done
	# create /usr/share/doc/linux-doc symlink
	cd "$pkgdir"/usr/share/doc; ln -s linux-doc-"$pkgver" linux-doc
}

# subflavors install in $subpkgdir
virt() {
	_package virt "$subpkgdir"
}

_dev() {
	local _flavor=$(echo $subpkgname | sed -E 's/(^linux-|-dev$)//g')
	local _builddir="$srcdir"/build-$_flavor.$CARCH
	local _abi_release="$(make -C "$_builddir" -s kernelrelease)"
	# copy the only the parts that we really need for build 3rd party
	# kernel modules and install those as /usr/src/linux-headers,
	# simlar to what ubuntu does
	#
	# this way you dont need to install the 300-400 kernel sources to
	# build a tiny kernel module
	#
	pkgdesc="Headers and script for third party modules for $_flavor kernel"
	depends="$_depends_dev"
	local dir="$subpkgdir"/usr/src/linux-headers-"$_abi_release"
	set_kbuild_timestamp

	# first we import config, run prepare to set up for building
	# external modules, and create the scripts
	mkdir -p "$dir"
	cp -a "$_builddir"/.config "$_builddir"/localversion-alpine \
		"$dir"/

	install -D -t "$dir"/certs "$_builddir"/certs/signing_key.x509 || :

	make -C "$builddir" \
		O="$dir" \
		ARCH="$(_kernelarch $CARCH)" \
		AWK="${AWK:-mawk}" \
		prepare modules_prepare scripts

	# remove the stuff that points to real sources. we want 3rd party
	# modules to believe this is the sources
	rm "$dir"/Makefile "$dir"/source

	# copy the needed stuff from real sources
	#
	# this is taken from ubuntu kernel build script
	# http://kernel.ubuntu.com/git/ubuntu/ubuntu-zesty.git/tree/debian/rules.d/3-binary-indep.mk
	cd "$builddir"
	find .  -path './include/*' -prune \
		-o -path './scripts/*' -prune -o -type f \
		\( -name 'Makefile*' -o -name 'Kconfig*' -o -name 'Kbuild*' -o \
		   -name '*.sh' -o -name '*.pl' -o -name '*.lds' -o -name 'Platform' \) \
		-print | cpio -pdm "$dir"

	cp -a scripts include "$dir"

	find "arch/$_karch" -name include -type d -print | while IFS='' read -r folder; do
		find "$folder" -type f
	done | sort -u | cpio -pdm "$dir"

	install -Dm644 "$srcdir"/build-$_flavor.$CARCH/Module.symvers \
		"$dir"/Module.symvers

	# remove unneeded things
	msg "Removing documentation..."
	rm -r "$dir"/Documentation
	find "$dir" -type f -name '*.o' -printf 'Removing %P\n' -delete
	local _karch="$(_kernelarch $CARCH | sed 's/x86_64/x86/')"
	msg "Removing unneeded arch headers..."
	for i in "$dir"/arch/*; do
		if [ "${i##*/}" != "$_karch" ]; then
			echo "  ${i##*/}"
			rm -r "$i"
		fi
	done

	mkdir -p "$subpkgdir"/lib/modules/"$_abi_release"
	ln -sf /usr/src/linux-headers-"$_abi_release" \
		"$subpkgdir"/lib/modules/"$_abi_release"/build
}

sha512sums="
3b089030dc23bd111989744618fdcb54424a3118110c5c87db41d4d374a2f52e283af4ca49d0740abffb3686e822b0f9c62ec067e898b96876961753da591536  patch-6.6.59.patch.xz
458b2c34d46206f9b4ccbac54cc57aeca1eaecaf831bc441e59701bac6eadffc17f6ce24af6eadd0454964e843186539ac0d63295ad2cc32d112b60360c39a35  linux-6.6.tar.xz
58bf9e84fb01f811f0cada7f7953d111908f0b0650648d6a3522061fe08c9fe284c9315515ae386189253e37d0c92419f78048d6568e2e426654b1e61010685f  0001-powerpc-boot-wrapper-Add-z-notext-flag-for-ppc64le.patch
763dcb40f698d43b0bb856f44493973e840b66efe62a8fd41a08b6e3fa38cf903e059d107be3735ab2f38a0f27bdb0262798e5e530a1905f96195cd8bcf62fdf  0002-x86-Compress-vmlinux-with-zstd-19-instead-of-22.patch
75f232b6becee7d36d360ffaf2aaa837d13518f9ec620ca159bcb2a0e98eb18a77631406a9b44244ea0164a7ed59fad583823909681e9b894a012f9d13365b69  0003-kexec-add-kexec_load_disabled-boot-option.patch
2956050bb332411d00a285e9656618f2e34b631492bbc19bef54d83a6e91b8531f4e18830b9313cfe52fbf8a8ca6fb76cf55b3ddd146ca3b977046cf2fd10cad  0004-objtool-respect-AWK-setting.patch
4b16f15b47b5e5835b926126e39723f519290469517875cfb2d2b857a93ad1344f0d1ba4b255289e20f4da9c867647526b344f752981cee0a48c51577badac3f  0005-powerpc-config-defang-gcc-check-for-stack-protector-.patch
5b5556d7f84632c5a426c116a9dada9d5d921ef91230ee27f6d7f8ffbd1418a85e457ba2e922051f33f66c01725f0a926bfd36a84ccad8094431dd57f6a8e989  0006-LoongArch-Change-SHMLBA-from-SZ_64K-to-PAGE_SIZE.patch
a8286ac0cbff0736ab7d5503a19034b11d69d1faa84316bef69087102a009c27b9f54daf9d55d55112e8eef4f239d1dd3a34fe1b55c1aa078ca638a85e0ded1b  lts.aarch64.config
2fd7ce3f044f72718b51c7db81bb0f720630a8a4164b97036bfe1a0816efc6903ca83f580543ea4bdca6031d912af9138c44f90722ceff8d5e928412ad23a609  lts.armv7.config
b2534172f8eeb14edb5855c59e806ce07fdfbc1a5a4fe206dd037f17aa21b894d927c1cdcf7c87bb364efd491bb226e3ee21e7f46d26a1afc05f9385260985eb  lts.x86.config
0b72ab5905e77b1c2f20ca03fc672f070389caf76fda0da80029703adf969750c53509399fb29af7c939da92918b08cec063bf460e1ad43a440c0c5c201d774b  lts.x86_64.config
fab6da1663ae24fa003a6771defe14db7ecc6d1ff86cded629e38078595a1e0f28389d12a120e7c3d738700670482cb0745114fc0701bf6dd58d31d67b3cf92a  lts.ppc64le.config
a436cc3f9e09452df392fe2274e4b55c00210ba3633e2fdd10494b61748f14fe3415ef94147f0f33885c4c6175a111628dadcae751a171162880fe14d5937ca9  lts.s390x.config
2c537aa0dae0fe619622947c6db94b6e0990a6ce2f854bf9228ee11b1fa5063c8f462e4442a210d56cbc4e6f7486788e7bc1f40e6f721f3ee351d109a128a2e7  lts.loongarch64.config
be02d493082977049c79ddb120f1213a712c3d73ef14c4225cf5dca1959044b1d8c8983690c3d59b7f14f9ac90dbd40088758342195e40bc0c464b457066d90b  virt.aarch64.config
12d1d8306e4834c90adf0e26ab28d15a2b7fcc1ce952bd5ad03703dd1e39bf6fd4742ba20376b8f9df5d65289df6e604beafc7f1e5f8a9abe607064becc482bd  virt.armv7.config
4380624b7b883944e27a8a07075e99046fc4349f6f4f3a9d6075e5076cba10c8d110a4921e6a6fe7ab6bc2cfd2b58435e8aa55db721c13ed5c27840b7c67f279  virt.ppc64le.config
38e5a475800ee72476fa77b66e61192e4b37b2aadd8f0813b1f4f3851d434116642cb71c36c9954746b828ad21b95890ed1c6c18b5af3f6c0a4c6177cf43fecf  virt.x86.config
9dff1781e3b56f32b072c2f354f8b8f9bea9e98a5d3daaf7db5e9316f12c40db3fbffe180e4489f5f2d8e9fd330d1c9e9993845f55e586812b096901499d3c4e  virt.x86_64.config
"
